There are many systems which require application of a low-temperature fluid at a location that is remote from the source of the fluid. In such systems, coolant hoses or lines are used to carry the fluid to the desired location. Typically, the fluid is circulated through the device being cooled. Hence, a pair of parallel coolant lines, an input line and an output line, are connected between the fluid source and the device being cooled.
For example, a semiconductor wafer prober machine used to electrically test semiconductor integrated circuits on a wafer can include the capability of temperature cycling a wafer under test. These machines typically include a wafer chuck used to hold the wafer in place while it is being tested. The chuck can include a heater and a heat sink for heating and cooling the wafer such that electrical circuit performance can be tested over temperature. The heat sink can include a fluid tube for circulating a low-temperature fluid near the wafer to cool the wafer. In this type of prober, the low-temperature fluid can be transferred from the fluid source to the prober machine. The coolant is then connected internally to the chuck. Such systems also include the capability of introducing a dry gas, such as air, nitrogen, or other gases, near the chuck to prevent condensation during low-temperature testing. A dry gas source can be provided inside the prober, or a separate gas dryer can be used.
Such systems typically operate in standard room ambient environments having typical room temperatures and humidities. As a result, when the low-temperature fluid flows through the coolant lines, condensation occurs and frost forms on the exterior surfaces of the lines. When the flow of fluid is interrupted, the frost melts, leaving pools of water on the floor.